Sprag type overrunning clutch



Oct. 21, 1952 R. M. HEINTz -A 2,614,670

SPRAG TYPE OVERRUNNING CLUTCH I 2 SHEETS-SHEET 1 V Aug. 14

INVENTOR.

'RALPH M. HEmTz ATTORNEY Oct. 21, 1952 R. M. HEIN-rz 2,614,670

y SPRAG TYPE OVERRUNNING CLUTCH Fi1e d Aug. 14, 1946 v 2 SHEETS- SHEET 2 .1 1: N 1 il uw ,I s l, y?

INVEN TOR.

RALPH M. HEmTz` ATTORNEY Patented Oct.` 2.1., 1952 sPnAG TYPEfovERRUNNING CL'TCH Ralph M. Heintz, cleveland, ohio;l assigner to `Jack & Heint'z Precisiin Indstries,-`lnc., Gleveland, Ohio, a corporation -of Delaware Application August '14, 1946, serial 510.690,29!)

This invention'relates in `general to overrunning, or one-way, clutches and more particularly to such clutches that employ tiltablefgrippers, or sprags.

Such clutches are frequently used in certain 3 ltypes ofr rotary `transmissions where power impulses from the driver occur in rapidsucceslsio'n with an interval between the succeeding impulses during which-the driver must -bedi`srconnected from the driven member.

It is, therefore, essential that the clutch be instantaneously connected as its -action may -be for a very small time interval. Another condition affecting the operation of the clutch is that it may be subjected to centrifugal force eccentric to its axis of revolution in which case the inertia of the clutching elements may interfere with instantaneous engagement. g

It is, therefore, an object of the present invention to providea rotary overrunning clutch capable of instantaneous engagement and disengage.

ment and which will4 be unaffected by other forces, such as eccentric centrifugal fo-rce.

Another object of the invention is to provide an overrunning clutch in which the sprags and spacers comprise a self-contained unit which may be handled as such.

A further object is to provide such a self-contained clutch sprag and spacer unit in which the spacers are of resilient material and molded to be a continuous single element extending throughholes in the sprags and molded to the sprags all to hold themin assembled position and control their tilting.

A still further object is to provide in` such a clutch, sprags of such improved contours that will so place their centers of gravity as to improve their capacity to become disengaged in an overrunning clutch position.

With the foregoing and other objects in view, the invention resides in the combination of parts and in the details of construction hereinafter set forth in the following specication and appended claims, certain embodiments thereof being illustrated in the accompanying drawings, in which:

Figure 1 is aview in end elevation, partly in section showing a preferred form ofthe clutch embodying the invention; y

Figure 2 is a similar end view enlarged of one sprag with its spacers between adjacent sprags; and

Figure 3 is a View in section taken along line 3-3 of Figure l.

Referring more particularly to the drawings, the clutch may be designed to connect an inner 1 claim. (ci. l1ere-45.1)

race l-and fan outer race 2 having spaced coaxial cylindrical surfaces. The inner rac'e may l'formed von its interior with one or more1`sp1ines 3 for connection to a shaft and the outer race may be formed on its exterior for mounting in any Asuitable velement to 'be 'connected to the shaft.

The clutch, which is adapted to yconnect'the inner Aand outer races, -in'clu'des faseries of tilt,- Aable gripping metallic fsprags i4 'that-are held 'spacedap'artfb'y a series of alternately arranged rubber-like *.iiexible resilient compressible non metallic spacers 51 with-which Athe, sprags 'are molded. Departing from the usual construction or employing separate spacer elements and r employing spring or lother tying elements to hold the assembled sprags and spacers together, the present invention contemplates the forming of parallel holes in each of the sprags and the molding of rubber, or compound containing rubber, into the form of spacers. In the molding operation the rubber spacers are molded together with the sprags. Moreover, the rubber extends through the holes in the sprags in the form of tying elements as shown at 6 and 'I so that the molded rubber element is integral to include the series of spacers 5 as well as the connecting rubber tying vlinks 6 and 'I'. In this manner the clutch is a virtually integral self-contained unit throughout its entire Llength and a unit which may be handled as such. As shown in Figure 1, the greatest diameter of each sprag is greater than the space between the races I and 2 and the greatest diameter of each spaceris apprecably less than this space to permit tilting of the sprags in contact with the two spaced races.

yFigure 2 illustrates the contour of one sprag and the relationship between its contour and that of its two adjacent sprags which are separated by spacers. The line of action tol engage the clutch involves the tilting vof the sprag about a fulcrum point 8 in a counterclockwise direction and the line of action to disengage the clutch of the middle sprag of Figure 2 to point I I of thel sprag on the right is the same length as that of line D from point I2 of the middle sprag to point I3 on the sprag to the left. This is an illustration of a preferred contour of each sprag and itsrelationship to the adjacent sprags determined by the normal contour of the intervening rubber spacers which space, and by means of the integral rubber tying portions and l' hold, the sprags iiexibly in place in the assembly. This places Yand determines the two points 8 and 9 of fulcrum for the sprags as they tilt into and out of clutching engagement with the inner and outer races.y Thefsprags all operate in unison so that the races will be gripped together uniormly throughout their circumferences.

Moreover, in addition to the molding of the spacers with the sprags, the rubber molding, being in one integral piece to include all the spacers and tying elements materially enhances uniformity of action of the sprags farv and above the conventional separate rigid spacers tied together by a continuous wire spring or other tying devices.

Figure 3 shows the assembly including the inner race and outer race in spaced relationship and the sprags 4, with the rubber molded tying elements 6 and l, and the retainer I4 and vsnap ring I for holding the clutch with its sprags and spacers in place.

I claim:

A unitary self-contained overrunning clutch for effecting a drive between radially spaced inner and outer rotative elements and comprising-a plurality of rotatably tiltable radially elongated sprags of rigid material, a plurality of spacers of non-metallic, elastic, resilient, Volumetrically compressible material arranged alternately between said sprags, each of said sprags being made of rigid metallic material, each of said sprags having a, hole extending transversely therethrough, relatively thin tying elements of the same elastic material as said spacers of appreciably lesser dimensions than those of said spacers extending through the hole of each sprag and molded together withreachv sprag to be integral with the spacers on both sides of each sprag tohold said sprags together both in tension and compression, the radial length of each tiltable sprag being greater than the space between said rotative elements and the greatest diameter of each ofl said spacers being less than said space to maintain said spacers out of contact with said rotative elements to permit rotatable tilting of said sprags. v

RALPH M. HEINTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,923,283 Stokes Aug. 22, 1933 2,342,227 Swenson Feb. 22, 1944 2,386,013 Swenson Oct. 2, 1945 2,407,772 Dodge Sept. 17, 1946 2,427,120 Blair Sept. 9, 1947 2,520,004 Gondek Aug. 22, 1950 2,555,484 Gruenberg et al. June 5, 1951 

